textproduct: Albany

WHAT HAS CHANGED

No significant changes with this update.

KEY MESSAGES

1) A widespread rainfall is expected late today through early Tuesday with the heaviest amounts likely across the mid-Hudson Valley into Litchfield County, CT. Isolated to scattered flash flooding will be possible, especially within urban and poor drainage areas.

2) Drier weather returns for the middle of the week with temperatures trending back above normal again later this week.

DISCUSSION

KEY MESSAGE 1...

A frontal boundary will be stalled just south of the region over the northern mid Atlantic States with waves of low pressure moving along this front through Tuesday. Rounds of showers and embedded thunderstorms are expected drift across the region by this evening and continuing into Tuesday Some areas will see repeated rounds of showers and thunderstorms, some of which can fall heavy at times, which will allow for a threat for excessive rainfall and flash flooding.

PWAT values are expected to increase to 1.50 to around 2.00 inches tonight and continue into early Tuesday. The values across southern areas are about 150%-180% of normal, which is about 2 STD above normal. Model soundings are showing plenty of signs for excessive rainfall, including a moist profile throughout the column, skinny CAPE profile, high PWATs and a high freezing level, indicating the potential for warm- rain processes and efficient rainfall production. Rainfall rates may easily exceed 1 inch per hour within thunderstorms with this setup. The 12z SPC HREF PMM 3hr totals shows pockets of 1-2 inches of rainfall within the high terrain of our southern areas, which are impressive amounts for an ensemble.

It remains uncertainty where the best corridor of heaviest rain sets up but the probabilities for this occurring are highest for areas south of Albany, especially across Ulster, Dutchess and Litchfield counties, where a Flood Watch for flash flooding remains in effect. WPC has also placed areas south of Albany in a slight risk for excessive rainfall (level 2 of 4) for Monday. There was not enough confidence in flooding concerns to expand the Flood Watch northward at this time but trends will be monitored. Within the slight risk area, flooding of urban and poor drainage areas are possible along with isolated to scattered instances of flash flooding. Total rainfall amounts of 1 to 3 inches remain possible south of Albany through Tuesday with localized amounts in excess of 3 inches possible, especially where repeated rounds of heavy rain occur.

KEY MESSAGE 2...

Nearly zonal flow returns to the region for the mid to late week period as high pressure builds in for Wednesday. This will bring a drier day to the area with near seasonable temperatures. Temperatures look to trend slightly above normal later this week with an uptick in humidity levels. An approaching low pressure system and cold front will bring increased chances for showers and thunderstorms for the end of the week as well.

AVIATION /06Z MONDAY THROUGH FRIDAY/

A large area of light to moderate rainfall is currently impacting much of NJ and downstate NY and this is lifting northeast. KPOU has been starting to see some of this rainfall, with MVFR visibility being reported. Based on upstream observations, will anticipate some locally heavy downpours there over the next few hours, with some IFR conditions possible. Have included a TEMPO based on this expectation. Further north, some light showers may get close to KALB/KPSF over the next few hours, but it will be dry for most of the time. Can't rule some brief MVFR showers at KPSF, but KALB should stay VFR, with no precip expected at KGFL, keeping VFR conditions there with just bkn-ovc high level clouds. Through the rest of the overnight hours, light east to southeast winds will be 5 kts or less.

During the day on Monday, steady light to moderate rainfall will continue for KPOU with MVFR conditions. Another period of IFR visibility is possible there during the afternoon hours once again, with some embedded heavier bursts. Meanwhile, the other sites will be mainly dry, but can't rule out some passing showers at KALB and KPSF, with perhaps some additional MVFR visibility at KPSF once again by the afternoon hours. All sites will be seeing gradually lowering ceilings, so even outside of rain, MVFR cigs are expected at KALB and KPSF by late in the day. KGFL will continue to be dry with VFR conditions. Some LLWS is possible for KPSF and KPOU during the day, with 2 kft winds around 35-40 kts from a southeasterly direction.

Rainfall will start to taper off for all sites on Monday night. Flying conditions will likely still be MVFR for sites thanks to lingering low level moisture keeping low ceilings around, although KGFL should continue to be the exception and remain VFR. Surface winds will be light to calm for all sites.

Outlook...

Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: High Operational Impact. Likely SHRA...TSRA. Friday Night: Moderate Operational Impact. Chance of SHRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...Flood Watch through Tuesday morning for CTZ001-013. NY...Flood Watch through Tuesday morning for NYZ063>066. MA...None. VT...None.